After slaughtering of pigs the ribs may be removed from the belly either as different kinds of spareribs where the meat between the ribs are removed together with the ribs or the ribs can be removed from the belly piece removing only as little meat as possible between the ribs i.e. removing all the ribs as single ribs and leaving as much meat at the belly piece as possible.
At many pig abattoirs single ribs are removed from belly pieces by a manual process where an abattoir worker either cuts away the single ribs by a knife or uses a manual rib puller e.g. with a loop-shaped element such as the one described in e.g. CH 597762 or a manual rib puller with a nylon string. Pulling single ribs by a loop-shaped element is also possible with a semiautomatic process e.g. by using a device as described in EP 0469680. Using a handheld tool with two knives cutting along a bone is described in CH 604536.
Pulling single ribs as a semiautomatic process using a pneumatic rib puller such as the one shown in FIG. 1, which is a prior art rib puller with a nylon string at the end of the puller makes it possible at a very high speed to pull single ribs from belly pieces when the end of the rib bones are exposed. This is a tough working situation for the abattoir workers as they have to use a finger to locate the string around the exposed end of the rib bone and with the same hand pressing and holding down the rib bone securing the rib bone is not lifted from the meat and does not break. It takes long time to learn to manage a pneumatic rib puller and not everyone can learn to use such a rib puller such as the one shown in FIG. 1, and manage it at the high speed necessary to handle all the belly pieces at the slaughter line. Also, if the string is not in the right position when the pneumatic tool is activated there is a risk of cracking the bone and increasing the number of bone splinters in the meat. The success of the pulling process with the prior art rib puller is depending on the abattoir workers coordination of correct location of the string beneath the exposed end of the rib bone, use of the counter hold to hold the belly piece in a suitable position, activation of the pull bar and support of the rib bone with the hand (carpus) during the pulling of the string, and all this should be done with a high speed.
The hand-held rib puller as described herein is much easier to manage than the prior art rib puller and it also reduces the working stress imposed upon the abattoir workers as it is much easier to bring the string in the correct position and also the pressure applied by the abattoir workers towards the belly meat pieces is very much reduced thus reducing the risk of physical disabilities for the abattoir workers.
For some kinds of meat cuttings machines have been developed which in a pure mechanically pattern remove bones from cuttings. Such machines are often removing a pre-determined amount of a cutting which may not be adjusted due to the variation in the meat cuttings such as variation in size of the bones and of the meat cuttings themselves. Too much meat may be removed in such a bone removal, which may add up to a huge amount of products which are sold at a lower price due to a lower weight.
In the automation of the process of removing bones from carcasses and cuttings, measuring systems are required to obtain information which can be used e.g. when the bone removing part of a system such as a robot removes the bones.
Herein is described a measuring or scanning system for determining presence and/or position of bones in a meat piece and especially of bones located near the edge in a meat piece, such as ribs in a belly piece. The measuring system may be a part of a larger system for removing detected bones, where the bones are automatically removed by an industrial robot. Such a system may be a system for removing near the edge bones e.g. ribs from a belly piece.
The rib puller as described herein may be constructed as a pneumatic rib puller and also as a tool for a robot such as an industrial robot. A measuring system for determination of the presence and location of bones such as ribs is also described, this measuring system can collect information and determine a working path which an industrial robot uses when removing bones from a meat piece such as ribs from a belly piece.